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51.
This research investigates the economic and social aspects of human–wildlife conflict (HWC) in Mhokwe, Mbire district, Zimbabwe. Data were collected through key informant interviews and a questionnaire survey. Most households in Mhokwe rely on crop and livestock production, and hence, HWC is an important factor affecting livelihoods. More than 60% of respondents experienced problems with lions (Panthera leo Linnaeus), spotted hyaenas (Crocuta crocuta Erxleben), armoured bush crickets (Acanthoplus speiseri Brancsik) and quelea birds (Quelea quelea Reichenbach). Other problem animals included elephant (Loxodonta africana Blumenbach), vervet monkey (Chlorocebus pygerythrus Cuvier), kudu (Tragelaphus strepsiceros Pallas), chacma baboon (Papio ursinus Kerr), bushpig (Potamochoerus porcus Linnaeus) and common duiker (Sylvicapra grimmia Linnaeus). Few incidences of conflicts were reported for hippopotamus (Hippopotamus amphibius Linnaeus), side-striped jackal (Canis adustus Sundevall), porcupine (Hystrix africaeaustralis Peters), nile crocodile (Crocodylus niloticus Laurenti), African wild cat (Felis lybica Forster), African python (Python sebae Gmelin) and guinea fowl (Numida meleagris Linnaeus). Livestock and crop losses were US$45,285 and US$57,541 in 2013 and 2014, respectively. Despite the losses, most respondents had positive attitudes towards wildlife. Construction of strong kraals and implementation of integrated pest management (IPM) can contribute to conflict reduction.  相似文献   
52.
目的:探究西安咸阳地区先天性心脏病危险因素的病例相关对照研究。方法:选择2014年1月至2019年1月于西安医学院第二附属医院及陕西中医学院第二附属医院进行治疗的常住地为西安咸阳地区8周以上孕妇为研究对象,将产前确诊为先天性心脏病(Congenital heart disease, CHD)孕妇列为病例组(68例),将排除CHD和(或)其他先天性疾病孕妇设为对照组(136例),对两组孕妇实施问卷调查,了解其家庭状况、孕妇情况、孕期环境污染、孕妇生活事件等因素与CHD发生的相关性。结果:经分析研究68例CHD胎儿产妇及136例对照组资料,按照α=0.05位水准,使用x~2检验对59个研究因素进行单因素分析,初步筛选出14个可疑危险因素(妊娠高血压、妊娠糖尿病、感冒发烧、孕早期接触农药、孕早期服用抗生素、孕早期服用解热镇痛药、孕早期接触射线、被动吸烟、吸烟、母亲不良精神史、不良生育史、先兆流产史、父亲年龄、母亲年龄),再通过二项分类Logistic逐步回归法实施多因素分析,最终得到吸烟、孕早期接触农药、母亲不良精神史、先兆流产史、感冒发烧5个危险因素。结论:孕早期是胎儿心脏发育的关键时期,如果母亲孕早期有不良精神史、感冒发烧、先兆流产史、接触农药、吸烟,会直接增加CHD发病几率,提示母亲孕早期应加强保健防护,重视孕早期检查。  相似文献   
53.
摘要 目的:研究2015-2018年重庆万州区女性人乳头瘤病毒(HPV)的感染状况、基因亚型及年龄分布。方法:选取2015年1月-2018年12月期间重庆万州区进行两癌筛查以及前来我院就诊的女性,共计1203例,采用PCR-反向点杂交法检测HPV感染情况,分析各个年龄段HPV的感染状况、各个年龄段HPV感染基因亚型以及各个年龄段HPV单一感染和多重感染情况。结果:接受HPV检测的1203例女性中共有457例出现HPV感染,感染率为37.99%,其中<30岁35例,感染率为36.84%;30~39岁117例,感染率为37.74%;40~49岁120例,感染率为35.82%;50~59岁127例,感染率为37.46%;≥60岁57例,感染率为45.97%,各个年龄段之间的HPV的感染率比较差异有统计学意义(P<0.05),457例患者中共有635个HPV感染基因,其中高危型感染基因共568个,占感染基因的89.45%,低危型感染基因共67个,占感染基因的10.55%。单一感染人数共333人,占总感染人数的72.87%,其中高危单一感染共301人,占总感染人数65.86%,低危单一感染共32人,占总感染人数7.00%。多重感染人数共124人,占总人数的27.13%。结论:2015-2018年重庆万州区女性HPV感染率为37.99%,其中≥60岁年龄段的女性HPV感染率最高,高危感染和单一感染为主要的感染类型。  相似文献   
54.
In the wake of the success of aerobic granulation in sequential batch reactors (SBRs) for treating wastewater, attention is beginning to turn to continuous flow applications. This is a necessary step given the advantages of continuous flow treatment processes and the fact that the majority of full-scale wastewater treatment plants across the world are operated with aeration tanks and clarifiers in a continuous flow mode. As in SBRs, applying a selection pressure, based on differences in either settling velocity or the size of the biomass, is essential for successful granulation in continuous flow reactors (CFRs). CFRs employed for aerobic granulation come in multiple configurations, each with their own means of achieving such a selection pressure. Other factors, such as bioaugmentation and hydraulic shear force, also contribute to aerobic granulation to some extent. Besides the formation of aerobic granules, long-term stability of aerobic granules is also a critical issue to be addressed. Inorganic precipitation, special inocula, and various operational optimization strategies have been used to improve granule long-term structural integrity. Accumulated studies reviewed in this work demonstrate that aerobic granulation in CFRs is capable of removing a wide spectrum of contaminants and achieving properties generally comparable to those in SBRs. Despite the notable research progress made toward successful aerobic granulation in lab-scale CFRs, to the best of our knowledge, there are only three full-scale tests of the technique, two being seeded with anammox-supported aerobic granules and the other with conventional aerobic granules; two other process alternatives are currently in development. Application of settling- or size-based selection pressures and feast/famine conditions are especially difficult to implement to these and similar mainstream systems. Future research efforts needs to be focused on the optimization of the granule-to-floc ratio, enhancement of granule activity, improvement of long-term granule stability, and a better understanding of aerobic granulation mechanisms in CFRs, especially in full-scale applications.  相似文献   
55.
BACKGROUND: Increasing bodies of evidence suggest that metformin may be beneficial in the primary prevention of colorectal cancer (CRC), and a dose–response relationship has been reported. However, long-term epidemiological observations between the treatment period, cumulative dose, and intensity of metformin and CRC are rarely reported. The aim of this study was to identify the association between the effect of metformin and CRC development in a nationwide cohort study. METHODS: This nationwide population-based study examined a cohort of 1,000,000 patients randomly sampled from individuals enrolled in the Taiwan National Health Insurance system. Patients with newly diagnosed type 2 diabetes mellitus (DM) between 1997 and 2007 were enrolled. A statistical variables, including the demographic data, treatment period, cumulative dose, and intensity of metformin use, was compared between patients developing CRC and those without CRC. RESULTS: This study included 47,597 patients. The mean follow-time was 7.17 ± 3.21 years. After adjustment, metformin use was an independent protective factor against CRC development (P < .001). Although the protective ability of metformin against CRC development was reduced during long-term therapy, the risk of CRC decreased progressively with a higher cumulative dose or higher intensity of metformin use (both P < .001). CONCLUSION: This study revealed that metformin use significantly reduced the risk of CRC in a dose-dependent manner in patients with type 2 DM in the Taiwanese population. However, a gradual decline in medication adherence may reduce the protective ability of metformin against CRC development during long-term therapy.  相似文献   
56.
The inflammatory microenvironment plays a critical role in the development and progression of malignancies. In the present study, we aimed to evaluate the prognostic value of lymphocyte-related inflammation and immune-based prognostic scores in patients with chordoma after radical resection, including the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and systemic immune-inflammation index (SII). A total of 172 consecutive patients with chordoma who underwent radical resection were reviewed. R software was used to randomly select 86 chordoma patients as a training set and 86 chordoma patients as a validation set. Potential prognostic factors were also identified, including age, sex, tumor localization, KPS, Enneking stage, tumor size, and tumor metastasis. Overall survival (OS) was calculated using the Kaplan–Meier method and multivariate Cox regression analyses. NLR, PLR, SII, Enneking stage, tumor differentiation and tumor metastasis were identified as significant factors from the univariate analysis in both the training and validation sets and were subjected to multivariate Cox proportional hazards analysis. The univariate analysis showed that NLR ≥1.65, PLR ≥121, and SII ≥370×109/L were significantly associated with poor OS. In the multivariate Cox proportional hazard analysis, SII, Enneking stage and tumor metastasis were significantly associated with OS. As noninvasive, low-cost, reproducible prognostic biomarkers, NLR, PLR and SII could help predict poor prognosis in patients with chordoma after radical resection. This finding may contribute to the development of more effective tailored therapy according to the characteristics of individual tumors.  相似文献   
57.
PURPOSE: To distinguish hepatocellular carcinoma (HCC) from other types of hepatic lesions with the adaptive multi-exponential IVIM model. METHODS: 94 hepatic focal lesions, including 38 HCC, 16 metastasis, 12 focal nodular hyperplasia, 13 cholangiocarcinoma, and 15 hemangioma, were examined in this study. Diffusion-weighted images were acquired with 13 b values (b?=?0, 3, …, 500 s/mm2) to measure the adaptive multi-exponential IVIM parameters, namely, pure diffusion coefficient (D), diffusion fraction (fd), pseudo-diffusion coefficient (Di*) and perfusion-related diffusion fraction (fi) of the ith perfusion component. Comparison of the parameters of and their diagnostic performance was determined using Mann-Whitney U test, independent-sample t test, one-way analysis of variance, Z test and receiver-operating characteristic analysis. RESULTS: D, D1* and D2* presented significantly difference between HCCs and other hepatic lesions, whereas fd, f1 and f2 did not show statistical differences. In the differential diagnosis of HCCs from other hepatic lesions, D2* (AUC, 0.927) provided best diagnostic performance among all parameters. Additionally, the number of exponential terms in the model was also an important indicator for distinguishing HCCs from other hepatic lesions. In the benign and malignant analysis, D gave the greatest AUC values, 0.895 or 0.853, for differentiation between malignant and benign lesions with three or two exponential terms. Most parameters were not significantly different between hypovascular and hypervascular lesions. For multiple comparisons, significant differences of D, D1* or D2* were found between certain lesion types. CONCLUSION: The adaptive multi-exponential IVIM model was useful and reliable to distinguish HCC from other hepatic lesions.  相似文献   
58.
OBJECTIVE: Asian melanoma patients, predominantly comprised of acral and mucosal subtypes, might not benefit from immunotherapy and targeted therapy as much as Caucasian patients. Novel treatment strategies are demanded after conventional treatment failure. This was a prospective, single-arm, and single-center dose escalation study to investigate the safety and preliminary efficacy of apatinib combined with temozolomide in heavily treated advanced melanoma patients. METHODS: Patients were sequentially admitted to four dose-escalating groups of apatinib and temozolomide (three cases in each group) using a traditional 3?+?3 dose escalation design method. RESULTS: Twelve patients were enrolled between December 2016 and August 2017. Most patients with an acral or mucosal primary origin progressed after immunotherapy or targeted therapy. Dose escalation had been completed without dose-limiting toxicity. Common adverse events included hypertension, hand-foot syndrome, proteinuria, neutropenia, nausea, and fatigue. All adverse events were grade 1 or 2, while the maximum tolerated dose was not reached. Up to January 2018, 1 patient achieved partial response, 9 experienced stable disease, and 2 exhibited progressive disease. The objective response rate and disease control rate were 8.3% and 83%, respectively. CONCLUSIONS: In conclusion, apatinib combined with temozolomide was well tolerated and has demonstrated efficacy in advanced melanoma patients.  相似文献   
59.
BACKGROUND AND PURPOSE: Breast cancer is now recognized as a clinically heterogeneous disease with a wide spectrum of epidemiological and clinicopathologic features. We aimed to evaluate whether epidemiological and clinicopathologic features are associated with the histological tumor grade of breast carcinomas in Western China. METHODS: We retrospectively collected data from the Western China Clinical Cooperation Group and assessed associations between clinicopathologic factors and histological tumor grade in 8619 female breast cancer patients. Patients were divided into two groups: Group I (tumor grade I/II) and Group II (tumor grade III). Univariable analysis and multivariable logistic regression models were used to analyze the relationships between clinicopathologic factors and tumor grade. RESULTS: Patients presenting with positive axillary lymph nodes, large tumor size (>2?cm), lymphovascular invasion, hormone receptor negativity, human epidermal growth factor receptor 2 (HER-2) positivity, and triple negativity tended to have an increased risk of a high tumor grade. However, the number of pregnancies or births was inversely correlated with the risk of a high tumor grade. In addition, patients presenting with grade III tumors were more likely to receive aggressive treatment, such as adjuvant chemotherapy, anti–HER-2 therapy, and level III axillary lymph node dissection. CONCLUSIONS: Our results suggested that several clinicopathologic factors were associated with high tumor grade of breast cancer patients in Western China.  相似文献   
60.
2022年7月在重庆市黔江区武陵山市级自然保护区采集到1号两栖动物标本,经形态特征比较,与尾突角蟾(Boulenophrys caudoprocta)相似;基于线粒体16Sr RNA和COI基因联合构建布角蟾属(Boulenophrys)部分物种系统发育树,此次采集的角蟾标本与尾突角蟾聚为一支,具有较高的支持率(1/100,贝叶斯法/最大似然超快速引导支持分析值);基于p-distance估算本次采集的角蟾标本与尾突角蟾湖南模式产地标本间的遗传距离为0%,远小于角蟾属物种间的遗传距离(8.7%~15.9%)。综合形态特征和分子系统发育比较,确定此次采集到的角蟾标本为无尾目(Anura)角蟾科(Megophryidae)布角蟾属的尾突角蟾,系重庆市两栖动物分布新记录种。重庆市尾突角蟾的发现,进一步扩展了该地区的物种名录,拓宽了对尾突角蟾分布范围的认知,为该属区系分类学和系统学提供了新信息,同时为当地生态系统和物种多样性的研究提供了基础信息,对制定更加全面和针对性的保护措施有着积极的促进作用。  相似文献   
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